1. Field of the Invention
The present invention relates to the field of respiratory therapy. More particularly, the invention concerns a respiratory apparatus operable for delivering a breathable gas to the airway of a patient and includes a status monitor for determining the status of usage of the unit by the patient and a timer for determining the accumulated time of usage of the unit by the patient.
2. Description of the Prior Art
In the treatment of obstructive sleep apnea, for example, it has been found that the application of pressurized ambient air to the nasal passages of a patient provides a pneumatic splint that maintains the patency of the airway. This type of respiratory therapy can be implemented by a home therapy device having a blower unit, a nasal mask, and a pneumatic hose interconnecting the two. When the patient is ready to retire for the night, the mask is placed in position over the patient's nose and the blower activated to deliver the prescribed therapeutic pressure regimen to the patient's airway. The prescribed therapy may include continuous positive air pressure (CPAP), intermittent positive air pressure (IPAP), or a variety of other pressure regimens, depending upon the needs of the patient.
As those skilled in the art appreciate, the effectiveness of an apnea therapy device depends upon its usage. In order to determine usage, some prior art devices have incorporated a timer which indicates accumulated operational time of the device. Such prior art devices, however, do not determine whether the device has actually been used by the patient. Even though the therapy device has been turned on, the patient may not have used the device or the nasal mask may have become dislodged during the sleep session.